1. Field of the Invention
The present invention relates to cooling fan and more particularly, to an improved structure of cooling fan that eliminates installation clearance to minimize friction and hard strength, avoiding operation noise and improving fan performance.
2. Description of the Related Art
A typical cooling fan for computer or the like, as shown in FIG. 1, generally comprises a bracket 1, a stator 11 affixed to the bracket 1, a winding 12 wound on the stator 11, a magnetic device 13 arranged around the winding 12, a bearing 14 mounted in the stator 11, an axle 151 coupled to the bearing 14, and a fan blade 15 affixed to the axle 151 for synchronous rotation. When electricity is provided to the winding 12, the winding 12 is energized to induce a magnetic field that acts upon the magnetic device 13, causing rotation of the fan blade 15 with the axle 151. According to this design, the bearing 14 is press-fitted into the stator 11, friction and hard strength are produced during rotation of the fan blade 15, resulting in a high noise level.
Therefore, it is desirable to provide a cooling fan that runs smoothly without producing much noise.